Generally most BBNC parts are not responsive by default. I've used jQuery to hack things so that I can get them the way I want them, but it's laborious and not recommended. I did recently style a default BBNC donate part and, although it's not technically "responsive,' it does render pretty good on smartphones and tablets. You can take a look here: https://maf.thankyou4caring.org/welcome (this page has a lot of other stuff on it too, but the donation form is near the top.